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(No Model.)

G. J. ATKINS. PROCESS 0F SEPARATING GOLD OR OTHER METALS PROM THEIRDRES.

Patented Oct. 25,1892.

vUNITED STATES PATENT OEEicE.

GEORGE J. ATKINS, OF LONDON, ENGLAND.

PROCESS F SEPARATING GOLD AND OTHER METALS FROM THEIR ORES.

SPECIFICATION forming part of Letters Patent No. 484,869, dated October25, 1892.

Application tiled April 28, 1891. Serial No. 390,865. (No specimens.)Patented in England September 28, 1886, No. 12,295; in France November24, 1887, No. 187,179 in Germany November 27, 1887, No. 45,774; in Capeof Good Hope December 9,1887,

No. 425; in Natal December 19,1887; in Canada December 20. 1887, No.28,212; in Victoria December 21, 1887, No. 5,528;

in New South Wales December 22, 1887, No. 403; in South Australia.December 24, 1887, No. 931; in Queensland December 29, 1887,No. 373; inTasmania December 29, 1887, No. 520/; in New Zealand January 4, 1888,No. 2,722; in India January 4,1888,N0. 235; in Spain April 27, 1888,Nos. 12,412 and 7,697; in Austria-Hungary May 13, 1888, No. 11,502 andNo.

49,944, and in Transvaal November 22, 1889, No. 140.

To @ZZ whom it may concern:

Be it known that I, GEORGE JONES ATKINs, electrician, a subject of theQueen of Great Britain, residing at Tottenham, London, in the county ofMiddlesex and Kingdom of England, have invented a new or ImprovedProcess of Separating Gold and other Metals from Their Ores, (for whichl have received Letters Patent in England, No. 12,295, dated September28, 1886; in France, No. 187,179, dated November 24, 1887; in Germany,No. 45,774, dated November 27, 1887; in Austria- Hungary, No. 49,944 andNo. 11,502, dated May 13, 1888; in Spain, Nos. 12,412 and 7,697, datedApril 27, 1888; in Canada, No. 28,212, dated December 20, 1887; inIndia, No. 235,

. dated January 4, 1888; in Cape of Good Hope,

No. 425, dated December 9, 1887; in Natal, dated'December 1 9, 1887; inQueensland, No. 373, dated December 29, 1887; in Tasmania, No. 520/10,dated December 29, 1887; in New Zealand, No. 2,722, dated January 4,1888; in Victoria, No. 5,523, dated December 21,1887; in New SouthWales, No. 403, dated December 22, 1887; in South Australia, No. 931,dated December 24, 1887, and in Transvaal, No. 140, dated November 22,1889,) of which the following is a specification.

This invention has for its object the separation of gold, silver, andother metals from theirores; and it consists in subjectingerushed orpulverized ore to eleetrolytic action in an electrolytie apparatusprovided with devices by which the said ore is retarded in its descentthrough the said apparatus, so as to keep the particles of ore in motionin the electrolytic solution forasuftieient period of time to allow theelectro-chemical action-such as oxidation, chlorinization, or treatmentwith cyanogen, for example-to take place, and in then subjecting the oreso treated to the action of mercury in an amalgamating apparatus whichis electrically connected with the cathode-pole of the said electrolyticapparatus.

In the drawings hereto annexed, Figure l is a vertical section of anelectrolytic and amalgamating apparatus suitable for carrying my new orimproved process into effect..

Fig. l* is asimilarsection of a modified form of the electrolytic partof such apparatus,

and Fig. 2 is a horizontal section on the linev plication, Serial Nos.390,864 and 390,866.

The crushed or pulverized ore is fed from a hopper or other receptacleinto a vertical chamber A, (see Fig. 1,) which forms theanode-compartment of the electrolytic apparatus. Revolving vertically inthis anodechamber is a shaft O, carrying a broad-bladed screw D,composed of carbon, lead, or anv other suitable material which is aconducteur of electricity but is not soluble in the electrolyticsolution employed. The edge of this screw approaches as near to thesides of the compartment A as possible, but preferably withouttouching,r them. On one side of the anode-chamber A is provided a filterE, of Woven matting, flannel, felt, porous plate, or other suitablewell-known material or combination of materials, which, While preventingthe passage of the gangue into the cathodecompartment B, still allows afree circulation of the electrolyte between the anode and cathodecompartments.

The cathode-compartment B :is provided with a cathode-cylinder H, ofcopper or other suitable conductive material, preferably mounted on arotating shaft G.

J are india-rubber or other flexible Scrapers secured in thecathode-compartment B for the purpose of removing the spongy orpulverulent deposit of metal from the revolving cathode-cylinder H as itis formed thereon. This spongy or pulverulent deposit is collected atthe bottom of tho cathode-compartment B and is periodically removedtherefrom 4through the opening K.

of a dynamo or other source of electricity and,

the` cathode-cylinder H with the negativepole of same. As the screw Dlrevolves in the anode-compartment A in the direction of the arrow itcauses the crushed or pulverized ore to be retarded in its descent inopposition to the action of gravity, (which latter tends to cause it todescend along the upper inclined surface of the screw D,) so as to delaythe descent of the particles of ore in the electro lytic solution and tokeep them in contact with the anode-screw for a sufficient length oftime to allow the process of oxidation, chlorinization, or other actionon the ore (according to the character of the solution employed) to beeffected by the anions liberated at the anode.

Instead of rotating the screw D in the direction indicated by the arrowin Fig. 1 it may be rotated in the opposite direction in cases where theelectrolytic action on the ore is sufficiently rapid to admit of it. Insome cases the screw D may remain stationary and the ore be caused toflow or roll down on the upper surface of it's thread by the action ofthe solution introduced at the top of theanodecompartment, such solutionpassing down through the anode-compartment and liowing olf therefrom bythe pipe Al, to be again returned to the top of the anode-compartment bya pump or otherwise, the gangueand any metal remaining therein passingaway from the anode-compartment through the passage M, as hereinaftermorefully described.

In some cases I substitute for the screw D in the anode-compartmentaseries of inclined ledges or shelves so arranged that theore in passingfrom the top to the bottom of the anode-compartment is caused to fallfrom one to the other of such ledges or shelves, which are composed ofmaterial similar to that em ployed for the said screw D, and, like it,act as the insoluble part of the positive or anode pole of theelectrolytic apparatus.` After having been freed more or less in theanode-compartment A from those metals which have been dissolved in theelectrolytic solution the pulverized ore, still containing the coarserparticles of gold, and in some cases silver as well, passesto the lowerpart of the anode compartment, which lower part is preferably taperedand opens into the pipe or passage M, leading to an amalgamatingapparatus which consists of a horizontal cylinder N, of cast-iron orslate, for example, with closed ends and containing a revolving drum O,earried by the shaft P, revolving in stuffingboxes and driven by apulley R. The periphery and sides or ends of the drum O tit more or lessclosely the interior of the cylinder N. Grooves or channels S are formedacross the periphery of the drum O, preferably in a more or less obliquedirection, and the spaces thus formed, as well as the clearance-spacesbetween the druln and'the cylinder, are lled with mercury high enough tocover the corru'gations in the surface of the drum O, so that the orefalls from the eleetrolytic apparatus directly onto the surface of themercury, 'a

well or sump T for a reserve of mercury bei ing also preferably providedat the bottom of the cylinder N.

The crushed or pulverized ore is introduced from the above-mentionedelectrolytic apparatus into the amalgamator through the passage M at oneend of the cylinder N, enters the grooves or channels in the peripheryof the drum O, and is carried down by the revolution of the said drum inthe direction of the arrow to the lower part of the cylinder N, throughthe mercury therein, and rises at the other side as the 'drum continuesits revolution, the oblique position of the groovescausing it togradually make its way to the opposite end of the drum after beingcarried round and round therein several times through the mercury, andit finally escapes from the grooves or channels in the periphery of thedrum by rising, on account ot' its inferior density, through the mercuryat an outlet-passage U at the opposite end of the cylinder N and passesaway by the spout V, any gold or silver being retained in the mercury,which is periodicallyor continuouslydrawnoffthrough the tap W and thegold and silver separated from it in the usual Way; or the pulverizedore may be delivered from the electrolytic apparatus into a tank orother vessel or place where it may be desired to deliver the ore thathas been treated in the electrolytic apparatus.

X is a reservoir, at the bottom of which is a pipe X', opening into achamber X2, connected by a pipe X3 with the mercury in the cylinder N.The lower end of the pipe X passes through a stuffing-box at the top ofthe chamber X2, so that thesaid pipe X', with the reservoir X, may beraised and lowered within certain limits by means of the bevelgearingX4, operated by a crank-handle. The bevel-wheel X4 is screw-threadedinternally, and the pipe X is screwed through it, so that as thecrank-handle is turned in one direction or the other the bevel-wheel X4is rotated likewise in its bearing and acts as a nut upon the screwedpart of the pipe X', raising or lowering the same with the reservoir X.When it is desired to increase the quantity of mercury in theamalgamating apparatus, so as to produce a greater head of mercury, andthereby to retard the tlow of ore from the electrolytic apparatus orother source of supply, the reservoir X and pipe X are raised and moreor less of the mercury fiows from the reservoir X into the cylinder N,and when it is desired to reduce the quantity of mercury in theamalgamating apparatus, so as to produce alesser head of mercury, andthereby to increase the flow of ore from the electrolytic apparatusorIOS IXO

other source of supply, the reservoir'X and with it some of the mercury.In order to facilitate its passage out of the apparatus and to preventit from carrying mercury with it, a rotary stirrerY may be employed,revolving in the hopper U at the upper end of the' outletpassage U anddriven by a belt from the shaft P or by other suitable means.

It will be understood that mercury may be introduced intoandwithdrawngfrom the amalgamator continuously, if necessary. Forexample, it may be taken by a pipe f from the bottom ofthe sump T andpumped by the pump b, which may be of any suitable kind, through astraining-box c, furnished with wash-leather or other suitable strainerc', and then allowed to How back into the upper part of theinlet CZ ofthe amalgamator through a pipe e. A by-pass may be provided to allow ofthe removal of the strainer containing the amalgam Without interferingwith the circulation of the mercury. It will now be understood that,vthe electrolytic compartments A B having been filled with one of theusual well-known electrolytic solutions, according to the nature of theore to be acted on and the result to be obtained, such as a solution ofsodium chloride, sodium sulphate, potassium cyanide, or ferro-cyanide ofpotassium, for example, the ore t-o be treated, after having beencrushed or pulverized vin the usual way, is introduced gradually andcontinuously through a hopper or other feeding device into the top ofthe anode-compartment A or A. The ore falls onto the retardin g-screw D,and gravity causes it to roll down the inclined surface of thescrew-thread; but as the latter is rotated, preferably, in the directionwhich tends to raise the said ore toward the top of theanode-compartment the passage of the ore from the top thereof to thebottom through the electrolytic solution is retarded and the whole ofthe ore is kept for a considerable time in contact with the anodepole,so as to form a more or less soluble portion thereof, while everyparticle is exposed to the action of the anions there generated. Theeect of this is that by the time the ore has reached the bottom of theanodecompartment all or part of the baser metals have been dissolved andthe gold left in or mixed with the gangue is in afree condition,

ready to be removed therefrom by the subse quent amalgamation process.The cations resulting from the solution of the metals in theanodecompartmeut A pass through the partition or lter E into thecathode-compartment B and are there deposited upon the cathode-cylinderH as a pulverulent metallic deposit, which is scraped od the cylinder Hby the Scrapers J, as above described, and ultimately falls to thebottom of the cathodecompartment, whence it is removed from time to timeor continuously for subsequent treatment or disposal, according to itsnature and other circumstances. The ore, with the gold or silver, orboth, having reached the bottom of the anode-compartment, passes to theamalgamatin g cylinder N or is otherwise dealt with, as beforeexplained.

It will be seen from the above description that the process ispractically a continuons one-that is to say, astream of crushed ore issupplied continuously to the anode-compartment, the baser metals areremoved from the surface of the gold as it passes through theanode-compartment, and the remaining ore and gold and silver may pass onto an amalgamating apparatus, Where the gold and silver may be separatedfrom the gangue in the manner well understood.

In some cases-as, for example, when treating ore containing aconsiderable quantity of silver-the ore which has been acted on in theanode-compartment A may be withdrawn from the bottom thereof and beintroduced into the top of the cathode-compartment B, which may also beprovided with a screw or other retarding device-such asa series of a1-ternating and overlapping plates O (shown in dotted lines, Fig.1)--simila'r to that in the anode-compartment instead of the cylinder H.The ore thus treated may then be withdrawn from the lower end of thecathode-compartment and be removed forsubsequent treatment byamalgamation or otherwise in separate apparatus, or it may pass directto amalgamating apparatus similar to that shown in Fig. 1, but placed atthe bottom of the cathode-compartment instead of at the bottom of the anode-compartment, and proper means must be provided for conveying the oreacted on in the anode-compartment from the lower end thereof to theupper end of the cathodecompartment. This arrangement is applicable, forexample, when treating ore containing sulphide of silver with asolutionof chloride of sodium in the anode-compartment. The sulphide of silveris chlorinized in the anode-compartment, forming chloride of silver andliberating the sodium which appears at the cathode. Then by taking thegangue containing the chloride of silver from the lower end of theanode-compartment and passing it through the cathode-compartment thesodium at the cathode-pole combines with the chlorine of the chloride ofsilver, liberating the silver in the metallic state, which is separatedfrom the gangue by passing it through the above-described or any othersuitable amalgamating apparatus. Any of the baser metals-such as copper,iron, or zinc-deposited in the cathode-compartment will assist theaction last described by combining with the chlorine of the chloride ofsilver, so as to liberate metallic silver, in the same way as thesodium.

In the arrangement of the electrolytic apparatus shown in Fig. l* onecompartment only is employed instead of two, as in Fig. l. In this casethe compartment A consists of a metal cylinder--of copper, forexamplewhich forms the cathode-pole. The screw D, similar to thatdescribed in reference to Fig. 1,forms the anode-pole, and this isincased in IOO IIO

and surrounded by a porous partition or lter E, of canvas, flannel,felt,or other suitable filtering material, for preventing the ganguefrom reaching the cathode-pole and from falling over the edge of thescrew. The ore vafter being treated in this electrolytic apparatus maybe passed directly to'an amalgamating apparatus similar to that shown inFig. 1,

placed at the lower end of the compartment A'.

In either of the arrangements above described the amalgamating apparatusis connected electrically with the cathodepole of the electrolyticapparatus or with the positive pole of a dynamo or other source ofelectricity, whereby such amalgamating apparatus becomes partof thecathode-pole of such electrolytic apparatus, so as to prevent thecorroding action of the electrolytic solution upon thesaidlamalgamatingapparatus when the same is formed ot metal-such lascastiron,.for example-and upon the mercu-rycontained therein when suchsolution is of a nature that would otherwise cause it to act upon them.This arrangement also preserves the mercury ina clean condition.

In Fig. 1a-represents1a positive pole formed of a ,block of carbon orother suitable conducting substance placed Yin the mouth of the outlet Uand insulated from.theamalgamating apparatus, such block a, being placedin electrical connection with lthe anode-pole of the electrolyticapparatusor with thenegative pole of a dynamo or other source ofelectricity, theanodepole D forming `the positive pole at the inlet ofthe amalgamating apparatus. This electric connection of the amalgamatingapparatus and of the mercurywith the electrolytic apparatus causes thedirect deposition in and amalgamation .by the mercurial cathode of partyot the gold and silver .contained in the solution, the remainder of thegold and silver being deposited upon the cathode of the electrolyticapparatus, from whence it is removed, in the case of Fig. 1,1;0 beafterward treated, or, as in Fig. 1*, falls into the mercury direct andis then amalgamated therewith. When a sodium solution is employed, avaluable sodium amalgam is formed in the amalgamatorby the directdeposit of the sodium ,into'the mercury.

I claim 1. The continuous process of separating gold andother metalsfrom their ores, which consists in passing such ore throughv theanodecompartment of anelectrolyticapparatus in contact with the anodeandretarding the descent of theore in the said anode-compartment while suchore is kept in contact with the anode-pole of such compartment, so as toform a more or less soluble portion of such anode-pole, and thensubjecting the one to the process of amalgamation,substantially as andfor the purpose set forth.

2. y The continuous process of separating gold and other metals fromtheir ores, which consists in passing such ore through theanodefcompartmentofV an electrolytc apparatus, retarding the desccntofthe ore in the said anode-compartment while such `ore-is kept in contact`withtheanosle-pole of such compartment, so as to ,form a more or lesssoluble portionof suche-node,pole,.thenpassingthe ore throughtheicathode-compartment, in retarding the descent thereof in the saidcathodecompartment, and then subjecting theone to the process ofamalgamation, substantially as and for the purpose set "fol-th.

In testimony that I claim the foregoing as my invention I ,haverlsignedmy name in presence'of two subscribingwit-nesses.

' GEORGE J. ATKINS.

Witnesses:

STEPHEN EDWARD LGUNYON, 115 Cannon Sweet, London, E. C';

WILLIAM ANDREW MARSHALL, 50 Londesbo rough Road, Stoke-Newington, lV.

